1. Field of the Invention.
This invention relates to filler pipe seals and more particularly filler pipe seals with a fill control skirt.
2. Description of the Prior Art.
Filler pipe seals have been known to sealingly connect a filler pipe to a fuel tank while allowing the filler pipe to slide into the fuel tank without disrupting the seal. These types of seals, made from elastomeric material, are found in many motor vehicles. One seal is disclosed in U.S. Pat. No. 4,088,241 issued on May 9, 1978 to Hall et al.
In the present fuel tank systems, the intruding end of the filler pipe determines the level at which fuel fills the tank. Trapped air in the tank, above the filler pipe end prevents fuel from completely filling the tank. Once the fuel level is at the end of the filler pipe end, the introduction of more fuel merely fills the filler pipe.
The conventional filler pipe seal, because it provides a sliding fit between the fuel tank and intruding end of the filler pipe, does not provide an accurate positioning means between the filler pipe and fuel tank. Due to manufacturing tolerances, the filler pipe intruding end may be set too low or too high from its intended position.
The manufacturing tolerance stack-up of a motor vehicle with a fuel tank and filler pipe can cause significant variations in the amount the end of the filler pipe intrudes within the fuel tank from one motor vehicle to the other to undesirably change the fuel tank capacity. If the filler pipe intrudes too deeply in the fuel tank, the fuel tank capacity is diminished and if the filler pipe is shortened so that it does not intrude enough, the fuel tank capacity is undesirably enlarged. Consequently, in mass production, two vehicles, both being the same design, can have fuel tanks with different fuel capacities.
It is desirable to build a fuel tank-filler pipe assembly that has a precise predetermined capacity while maintaining the sliding fit of the filler pipe into the fuel tank opening. Such an assembly is desired so that all fuel tanks of one motor vehicle model can be accurately standardized.